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Getting your vitamins?

Getting Your Vitamins?

Genny Gentry, a Tucson businesswoman, doesn't drink much milk. So, every night for several years, she took American Health Plus "Origin" supplements containing calcium and magnesium with chelated zinc.

That is, until she heard that if a calcium supplement fails to disintegrate in vinegar, it probably won't disintegrate in your body. Her Origins flunked the vinegar test.

On September 11, 1989, Gentry sued American Health Plus and the Osco Drug store chain for fraud and negligence.

What Gentry learned the hard way would be news to most people. Drugs must be tested to ensure that they are potent and that they can be used by your body. Vitamins and minerals need not be.

We probably wouldn't know much about supplements that fail to dissolve if it weren't for Ralph Shangraw, Chairman of the Department of Pharmaceutics at the University of Maryland.

One day in September 1986, Shangraw was experimenting with calcium salts as fillers for tablets and capsules when he noticed something strange.

"To my surprise and dismay, I discovered that not only did the calcium not dissolve from some commercial tablets," says Shangraw, "but that in many cases, the tablets took as long as four to six hours to disintegrate."

If a calcium carbonate tablet doesn't disintegrate by the time it leaves your stomach, chances are it won't get absorbed into your bloodstream.

Throughout 1987, Shangraw blew the whistle on calcium supplements that failed to disintegrate. Since then, many calcium-makers have cleaned up their act. But the experience led Shangraw to wonder about other supplements.

"I was somewhat surprised that many of the principles of product quality which are accepted as commonplace in the manufacture of pharmaceuticals are rarely if ever considered in many vitamin and mineral products," he says.

One of the first "principles of product quality" is that the supplement must disintegrate and its ingredients must dissolve while it's still in the digestive tract.

Had Your Cement Today? How do you know if a drug or supplement ever makes it into the bloodstream? Blood tests are best, but they can be expensive and difficult to perform.

Instead, the U.S. Pharmacopeial Convention (USP)--chartered by Congress to set standards for drugs--often settles for other laboratory tests. For most drugs, it requires pills to either disintegrate (break into small pieces) or be at least 50 or 75 percent dissolved after being agitated in simulated stomach or intestinal juice for a specified length of time.

But disintegration is only a minimal standard. "Tablets that do disintegrate may not get into the bloodstream," says Shangraw. "But if it doesn't disintegrate, that's a pretty good indication that it won't get absorbed."

Yet in 1986, says Shangraw, "more than half the calcium supplements in the marketplace failed to disintegrate within 30 minutes." What went wrong?

Shangraw has identified several problems:

* To keep their tablets as small (and swallowable) as possible, some companies compressed them too hard.

* Starch helps the tablets disintegrate, but some manufacturers removed it--probably so they could boast "no starch" on the label.

* Many companies coated their tablets with shellac, which resists stomach acid. (Shellac may be added to "all-natural" supplements, since the FDA considers it a natural ingredient.)

* When a drought in Africa made it hard for manufacturers to get the acacia gum used to hold tablets together, they switched to a more acidic gelatin, which, when mixed with calcium carbonate, made something resembling cement.

"To the industry's credit, they have as a whole reformulated and are now marketing acceptable calcium supplements," says Shangraw.

"But there may still be disintegration problems with these big calcium-magnesium-zinc tablets," says Michael Mayersohn, the University of Arizona pharmaceutics professor who confirmed that Genny Gentry's supplements were not disintegrating.

Tilt. If the industry could make so many errors with calcium, could it be doing the same with vitamins, minerals, and other supplements?

"I have seen X-rays of my lower gut with a perfect picture of an undigested multi-vitamin just as it was when swallowed," says Steven Brinkerhoff, a Nutrition Action reader from Covina, California. "My wife is a dental hygienist, and she had a patient who found a layer of vitamin pills in the bottom of his septic tank."

Shangraw has tested only a handful of multi-vitamin-and-minerals (see chart). Six out of 14 took more than one hour to disintegrate, and two--Thera-M and Theradex M--took 2-1/2 to 4-1/2 hours.

No one knows how quickly multi-vitamin-and-mineral supplements have to disintegrate in order to be absorbed. But finding out would cost a pretty penny.

So Shangraw takes a practical approach. "If we have the capability of making tablets that disintegrate within 20 to 25 minutes--and at approximately the same price--why not produce them?"

Windmill Inc., of Fairfield, New Jersey, makes more than 1,500 supplements which are sold under 30 to 40 different brand names. Ted Korab, Windmill's technical advisor, says his company's multi-vitamins have to disintegrate within two hours. Why two?

"If you look at USP's standards, many uncoated products call for a 30-minute disintegration," says Korab. "If it's coated, it can take an additional 60 minutes. Our in-house standard is a half hour longer."

But for Windmill's uncoated multi-vitamins, its in-house standard is actually 1-1/2 hours longer than USP's. And why allow a standard that's even a half hour too long?

"We don't have to conform to USP," says Korab. And he's right. No supplement manufacturers have to.

No Flushing, No Niacin. Vitamins that are designed to dissolve slowly pose a different problem. For example, the large doses of niacin that many people take to lower their cholesterol can cause flushing if the vitamin enters the blood-stream all at once. So consumers rely on sustained-release niacin.

But when Shangraw tested five sustained-release brands, two weren't even half dissolved after 12 hours. "The most important fact is that a product which has the slowest release might be viewed by the patient as being the best, because it would no doubt no flushing," says Shangraw. "But does the niacin ever enter your blood-stream? I think not."

Supplements that contain only water-soluble vitamin C or the Bs are not likely to have trouble dissolving, as long as they're not sustained-release. Shangraw hasn't tested many fat-soluble vitamins, but he did find one vitamin E tablet that took more than three hours to disintegrate. Fortunately, most vitamin E comes not in tablets, but in capsules, which dissolve more easily.

Minerals are also an unknown. Shangraw found one batch of iron tablets that took more than four hours to disintegrate. In another batch of the same brand, some tablets took four hours while others took only two.

Aiming Low. Dissolvability is not the only quality one expects in a supplement. Another is potency.

"We haven't begun to look at whether what's on the label is in the product," says Shangraw. "I can guarantee that some of these supplements are difficult to formulate. The components react with each other and decompose over time."

He notes that of the 12 FDA recalls of defective supplements in 1989, one involved a number of subpotent products made by pharmaceutical giant Eli Lilly.

"If Lilly is having trouble with potency, you can bet other companies are," says Shangraw.

Twelve recalls aren't very many. "But I'm more inclined to believe that it's a case of too few standards and even fewer people determining if marketed products meet them," he adds.

Ron Thompson, of General Nutrition Centers (GNC), knows that some of his competitors' products don't deliver what the label claims. He knows because GNC tests them.

"We find some with less than what's on the label, either because their potency is dropping, or because they were formulated low," he says. "Why shouldn't some manufacturers formulate to something below 100 percent? Their chances of getting caught are slim."

In fact, the FDA requires supplements to contain 100 percent of the nutrient levels listed on the label.

As Time Goes By. With time, supplements can decompose or become too hard to dissolve. So stability is the third quality they should have. Yet the FDA doesn't require expiration dates.

According to the FDA's Raymond Newberry, the problem isn't that serious, because most large brands sold in drug stores and supermarkets use expiration dates. But of the 48 brands we found at one local health-food store, 35 had no date.

What's more, expiration dates on supplements may not mean much. "Prescription drugs carry expiration dates that have to be backed by stability tests," explains Shangraw. Expiration dates on vitamins and minerals do not have to be.

Foods or Drugs? Because Shangraw's tests are so spotty, no one knows how often supplements are undissolvable or subpotent. But his results are disconcerting, especially because so many people use vitamins and minerals to prevent or treat disease.

"Calcium supplements are used in the treatment of osteoporosis and are reported to be effective in some types of cancer and hypertension," notes Shangraw.

"Iron is used to treat anemia. Niacin has proven effective in lowering cholesterol. The line dividing vitamins and minerals from drugs is gradually becoming less clear."

But GNC's Ron Thompson says that if companies make supplements using drug standards, prices would soar. "If we start manufacturing multi-vitamins with the same quality as drugs, the consumer would lose out. If I could sell 90 multi-vitamin tablets for $39.95, I'd treat them like a drug."

What's tough about making drugs is that every tablet has to be uniform. But when you mix 20 vitamins and minerals together in a blender, they don't always disperse evenly.

"If you're dealing with blood-pressure medication, you need the same amount in each tablet," says Thompson. "But it's not life-threatening if you get 10 micrograms of vitamin B-12 one day and 20 micrograms the next. If, over the aggregate, consumers are getting 15 micrograms, they're not getting cheated."

Okay, so supplements don't have to be as uniform and pure as drugs. But shouldn't they have to meet some standards?

Are Standards The Solution? Last March, after urging by Shangraw, the Pharmacopeial Convention voted unanimously to set standards for supplements.

The Council for Responsible Nutrition, which represents supplement-makers, likes the idea of standards, but is worried that some may be unnecessarily stringent.

"The question is, what kinds of tests are appropriate for what kinds of products?" asks the Council's Annette Dickinson. "It's technically feasible to make tablets that disintegrate within 10 minutes, but is it necessary?"

Also, the law requires only drugs to meet USP's standards. Legally, vitamins and minerals are not drugs, so the USP may have to rely on marketplace competition. In other words, if one niacin label says "Meets USP Standards," other companies might feel their products also have to.

New standards should keep the supplement industry from repeating its calcium mistake. But unless the FDA enforces the standards, there's not guarantee that what you buy is what you get.

"It would be nice if standards could result in marginal manufacturers being forced to comply or get out of business," says Thompson. "But the FDA doesn't have the manpower to pursue them. Some are in and out of business so quickly; it's like chasing smoke."

On the other hand, USP's standards may make it easier for the FDA to act, since the agency can recall or even seize supplements that fail to meet "good manufacturing practices."

Meanwhile, consumers are left--as usual--in the lurch. "I feel like I don't know if I'm wasting my money or not," says Nutrition Action reader Steven Brinkerhoff.

"I can't keep getting X-rayed to find out."
COPYRIGHT 1990 Center for Science in the Public Interest
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Copyright 1990, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

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Title Annotation:vitamin & mineral supplements that don't dissolve properly
Author:Liebman, Bonnie
Publication:Nutrition Action Healthletter
Date:Jun 1, 1990
Previous Article:Halloween candy: witch are better.
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